It's a pity you can't get the British Eurosport satellite feed over there - their GP commentary team is Toby Moody and Julian Ryder who crack me up but also really know their stuff, as lifelong GP fans, plus with Randy Mamola in the pit lane covering the MotoGP class.
For WSB they have Jack Burnicle and Niall Mackenzie (ex GP rider, 4 times BSB champion at the very recent end of his career), which is also pretty funny on occasions.
Meanwhile, the BBC use Suzi Perry as anchor on their WSB coverage, Charlie Cox (Australian, brilliant commentator, ex famous racing driver) supported by Steve Parrish (GP rider in the Sheene/Roberts era, recent truck racer and well known prankster). Again, they do a really good job.
I've watched some of the recycled Speed Channel AMA coverage on 'Motors TV' over here and their commentators all sound like they are doing too much caffeine, but also they don't seem to know WTF they are talking about either...
It's a pity you can't get the British audio feeds over in the states, I think a lot of people would prefer them.